Page:Popular Science Monthly Volume 41.djvu/137

 the best features of the most recent indexes, and will be a thoroughly practical guide to the store of information which the volumes of the magazine contain. The compiler is Mr. Frederik A. Fernald, of the editorial staff of the Monthly.



contents of this volume consist of essays and addresses prepared for various occasions and embracing a considerable range of topics. Among those dealing with natural science are a review of Goethe's Farbenlehre, a magazine article on Atoms, Molecules, and Ether Waves, another with the title About Common Water, and a paper on the Origin, Propagation, and Prevention of Phthisis. Tyndall's well-known power of making scientific subjects luminous and fascinating is abundantly shown throughout this volume. Take this passage from About Common Water:

The most striking example of the color of water is probably that furnished by the Blue Grotto of Capri, in the Bay of Naples. Capri is one of the islands of the bay. At the bottom of one of its sea-cliffs there is a small arch, barely sufficient to admit a boat in fine weather, and through this arch you pass into a spacious cavern, the walls and water of which shimmer forth a magical blue light. This light has caught its color from the water through which it has passed. The entrance, as just stated, is very small, so that the illumination of the cave is almost entirely due to light which has plunged to the bottom of the sea, and returned thence to the cave. Hence the exquisite azure. The white body of a diver who plunges into the water for the amusement of visitors is also strikingly affected by the colored liquid through which he moves.

The wonderful style above illustrated contributes a great part to the effectiveness of Prof. Tyndall's teachings in science. Many a student, using one of Tyndall's treatises on Heat, Light, or Electricity as a text-book, has found himself drawn on to read far beyond the limits set for the next lesson. Obviously the books that get themselves read are the ones that produce results; hence it is probably safe to say that no book has done more to spread an understanding of the nature and behavior of one of the great forces of Nature than his Heat as a Mode of Motion.

Tyndall is still more fascinating and becomes even inspiring when he discourses of his favorite recreation, climbing the Alps. There are two essays dealing with Alpine experiences in this collection, and many of the phenomena of glaciers, snow-fields, and mountain mists are introduced into the scientific papers. The following is a description of the sort with which his Alpine chapters abound:

At half past one o'clock on the morning of the 11th we started from the Wengern Alp. No trace of cloud was visible in the heavens, which were sown broadcast with stars. Those low down twinkled with extraordinary vivacity, many of them flashing, in quick succession, lights of different colors. . . . Over the summit of the Wetterhorn the Pleiades hung like a diadem, while at intervals a solitary meteor shot across the sky. We passed along the Alp, and then over the balled snow and broken ice shot down from the end of a glacier which fronted us. Here the ascent began; we passed by turns from snow to rock and from rock to snow. The steepness for a time was moderate, the only thing requiring caution being the thin crusts of ice upon the rocks over which water had trickled the previous day* The east gradually brightened, the stars became paler and disappeared, and at length the crown of the adjacent Jungfrau rose out of the twilight into the purple of the rising sun. The bloom crept gradually downward over the snows, until the whole mountain world partook of the color. It is not in the night nor in the day—it is not in any statical condition of the atmosphere—that the mountains look most sublime. It is during the few minutes of transition from twilight to full day through the splendors of the dawn.

Among the New Fragments are several biographical sketches, and these are fully as vivid as the essays already mentioned. The power of expression that can so greatly enliven inanimate objects is naturally no less potent in dealing with subjects that have lived. It is well for science that Tyndall's bent was turned so strongly toward scientific matters, for otherwise biography would long since have monopolized him. In reading his sketch of Count Rumford one is made to feel that the investigator of a century ago was also a man, and, moreover, what manner of man he was. The same applies to the account of Thomas Young; and when our author speaks of one whom he has known in the flesh, as in his Personal Recollections of Thomas Carlyle, and his address on unveiling the statue of Carlyle, the image of his subject stands out with marvelous distinctness.

Among the miscellaneous papers in this 